Layers of Sound

When listening to field recordings, people soon recognised that animals communicated to each other using different pitch ranges.

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Natural Frequency Selection

Explore the soundscape above, which has been split into separate frequency bands. Roll your mouse over each animal to hear their sounds.

This is a natural soundscape, within which each creature can be found calling in a different discrete band. Animals use these discrete bands so that they are not interrupted by other animals. Each animal calls out within its own niche.

Fact

The researchers who noticed that this banding occurs in nature gave it the name ‘Niche Hypothesis’.

Niche

A small gap.

Hypothesis

A theory based upon some evidence that encourages further thinking.

Because sound wave vibrations can interfere and overpower one another where they overlap, animals evolved to separate their call sounds into different bands of frequency so as to avoid (or reduce) this overlapping.

Birds

Low Frequency

Cows

The Same Is True in Music

This idea also works within music. Orchestras and pop bands have evolved to contain a range of instruments so that they can fill all the different frequency bands (low to high). Where sounds exist in the same frequency band, they often have a different timbre (so that they do not overlap).

Composition Tip

Avoiding overlapping can be very useful for retaining clarity in our own compositions.

Make sure that your sounds do not overlap too much.

If you have sounds in the same frequency area, make sure that they have different sound qualities and perhaps pan them apart.

As more and more creatures/instruments vie for a limited acoustical space, the ability to clearly stand out against the rest of the soundscape becomes even more important to each species’ survival.

Extra

Sometimes animals change their natural sound patterns to avoid this overlapping process depending upon their environment. One example of this is where birds change their singing patterns in city soundscapes. The city is very loud and noisy (with sounds at a wide range of frequencies) and it has been shown that where there are many low frequencies, some birds adapt to sing at a higher pitch.

Considering the Whole Soundscape

But while we can focus in on individual points and events within the soundscape, it is also really important to recognise how all of the elements fit together and only make complete sense when they are all heard as a whole.

We can compare this to only listening to the drum pattern of a pop song, ignoring all of the other instruments and voice. When we only focus on one aspect, we miss out on the many relationships between sounds and their context.

Fact

The phrase, “Can’t see the wood for the trees” also demonstrates this same effect.

If you are paying a lot of attention to individual details, you might miss out on the bigger picture.

Thinking about how the different parts of a soundscape fit together can be really useful for us when seeking to understand a soundscape, and can provide inspiration for our own creative practice, where we create musical works (in any genre).